Base maps/ ignition timing

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Hi, so i have a Version 10 WRX and was wondering how close the base map that comes in the link software is to a stock wrx map.

Basically i had an engine built and tuned by a friend not long ago and it has been knocking / detonating really badly and destroyed 2 pistons and possibly more. I know that the AFR's were fine as i installed a brand new sensor. Im leaning towards the ignition timing being horribly wrong because there didn't seem to be any huge problems in the way the engine was assembled and if that's true then the problem must be the ignition timing map. Below is a picture of the base map that comes with the link software (bottom) side by side with the map created by my friend (top). I have no idea about tuning ignition timing but i feel like there is way too much timing in the high map/high revs. I also know he didn't tune this using any kind of knock detection, another reason why i believe this is what has destroyed my engine.

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It doesnt look all that much more aggressive than the other one to me, the best thing you could do is to run a stock map and datalog your car so everyone can see what areas of the ignition and fuel map are in use, some areas almost never get touched.

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There are variables of course but also rules of thumb, and that’s way too much advance in the peak torque, high MAP area for a WRX on pump gasoline in my opinion. The Link table looks like a great safe starting point, the shape is much better with low timing at peak torque ramping up at high rpm.

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It doesnt look all that much more aggressive than the other one to me, the best thing you could do is to run a stock map and datalog your car so everyone can see what areas of the ignition and fuel map are in use, some areas almost never get touched.

It has an extra 7deg of timing in places...assuming all sensor scalings etc are correct and it is running in the correct load cells etc. ( possibly big assumptions ). So yes, it is very much more aggressive than the base map.

Certainly enough that it's destroyed 2 pistons although it could be down to many tuning related factors...but one single incompetent tuner factor.

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On alcohol that could be a non issue, again it comes down to the mods, and the turbo size, some of those areas would never even be usable by my setup! He needs to run a map tracer so that we know what areas are actually being seen by the ecu, engine damage could have happened by any number of things in the past, an air leak or poor quality fuel etc can take pistons out, who knows. There are also areas in his tuned map that are less aggressive than the provided stock map so it comes down to input from him.

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Ok, so some more info and an update. The car is running on 98 and has never had anything else in it. The turbo is a gtx3076r, the engine was run-in a couple months ago. It was running on 1 bar of boost (gate pressure) for that time, about 1500-2000kms. The day the engine failed, we were out road tuning. We increased the boost to 20psi, did multiple pulls to make sure it was steady and then started tinkering with the timing, he claims he heard a knock in his headset once during a pull and dropped the timing down where he thought it knocked, we did a few more pulls and he said it was still knocking in the same spot, he dropped some more timing in and around the same area and we did 1 more pull, 3rd to 4th, we hit the end of 4th gear and i clutched in and put it in neutral and it stalled instantly. He told me to roll-start it and it was knocking really bad so i turned it off straight away, we pulled over and there was smoke coming out of the breathers. He told me it spun a bearing and said it was my fault because he claimed i didn't put enough oil in it. I had an actual engine shop pull it apart, they told me the bearings are fine and that the pistons in cylinders 2 and 4 were destroyed. My guess is that because of the increase in manifold pressure it was going to areas of the ignition map that it wasn't before and those areas were too aggressive, causing it to knock itself to pieces.

I was quoted 6k for the engine shop to rebuild it. Lesson learnt, don't listen to people that tell you they know how to tune unless they can prove it beforehand.